Among US women who are pregnant, moving to a new residence during the first trimester may be a risk factor for adverse birth outcomes, including low birth weight and preterm birth, according to a study published in the Journal of Epidemiology and Community Health.
Researchers conducted a retrospective cohort study using Washington State birth certificate data that included parental demographics, maternal reproductive history, prenatal care, and infant birth information. Singleton births to mothers aged ≥18 years in Washington between 2007 and 2014 were included. Women who provided a residential address, length of time at residence, and a clinical estimate of gestational length were eligible for inclusion; a total of 28,011 women who moved during the first trimester of pregnancy were matched to 112,367 women who did not move.
The outcomes of interest were low birth weight (<2500 g), preterm birth (<37 weeks), and small for gestational age (lowest 10% of births for gestational age and sex). The researchers also examined very preterm birth (gestational age <32 weeks).
Women who moved during the first trimester of pregnancy were more likely than women who did not move to be in their teenage years or 20s (69.5% vs 55.9%), to not have completed high school (15.5% vs 13.6%), to live in a household with a median income <$40,000 (41.8% vs 35.8%), and to be nulliparous (49.3% vs 41.0%). Women who moved were also more likely to have smoked during pregnancy (11.9% vs 8.9%).
Moving in the first trimester was associated with an increased risk for low birth weight (6.4% compared with 4.5% of nonmovers); moving also was associated with an excess of 14 low birth weight deliveries per 1000 births compared with the nonmoving group. In addition, moving was associated with preterm birth (9.1% compared with 6.4% of nonmovers); compared with the nonmoving group, moving was associated with an additional 24 preterm deliveries per 1000 births. The prevalence for small for gestational age deliveries was slightly higher among movers vs nonmovers (9.8% vs 8.7%).
“Because up to 25% of pregnant women are estimated to move during pregnancy, elucidating associations between moving and adverse birth outcomes has the potential to impact the clinical care of many women and have an important impact on public health,” the authors concluded.
Bond JC, Mancenido AL, Patil DM, Rowley SS, Goldberg J, Littman AJ. Residence change during the first trimester of pregnancy and adverse birth outcomes [published online July 30, 2019]. J Epidemiol Community Health. doi:10.1136/jech-2018-211937